The goal of this proposal is to determine whether ligands for Trace Amine-associated Receptor 1 (TAAR1) are wake-promoting and pro-cognitive in non-human primates as we have found in laboratory rodents. Recent identification of selective agonists for TAAR1 that exhibit pro-cognitive, antidepressant- and antipsychotic-like properties in both rodent and non-human primates suggest TAAR1 is a novel target for the treatment of neuropsychiatric disorders. In collaboration with scientists from F. Hoffmann-La Roche, we have described brain-penetrable compounds with high potency and selectivity at mouse, rat, monkey and human TAAR1. Moreover, we showed that TAAR1 agonism causes a dose-dependent increase in wakefulness in rats and have replicated this effect in mice. Given the widespread occurrence of sleep disorders, we will further test the hypothesis that TAAR1 agonism is a novel therapeutic pathway to promote wake and enhance cognition. First, we will determine whether TAAR1 agonism promotes wakefulness in Cynomolgus macaques under conditions of both high and low sleep pressure. Although TAAR1 agonists increase vigilance in rodents, these animals are nocturnal and have polyphasic sleep/wake cycles in comparison to the consolidated periods of sleep and wakefulness characteristic of both humans and non-human primates. Implementation of EEG recording in these studies will enable us to determine the effects of TAAR1 agonism on NREM and REM sleep and to conduct quantitative EEG (qEEG) analysis to assess the effects of these compounds on EEG frequencies associated with cognition such as gamma oscillations. Next, we will test these compounds for their ability to improve working memory functions in macaques under baseline and sleep deprivation conditions. Working memory function is dependent on prior sleep history and subject to decline in aging, stress and in diseases such as schizophrenia and Alzheimer's disease. We have shown previously that TAAR1 agonists improve executive functions (e.g., response inhibition, planning) in non-human primates and in a rodent PCP-induced deficit model, however, this represents only one cognitive domain that can be affected in sleep disorders. Simultaneous assessment of behavior and qEEG in macaques performing the working memory task will enable investigation of cognitive function at both behavioral and electrophysiological levels. The results of these studies will aid in establishing TAAR1 agonism as a novel mechanism to enhance wakefulness and cognition in humans.